Opinion statement

Chronic myelomonocytic leukemia (CMML) is an aggressive myeloid neoplasm in which treatment strategies with the capacity to improve survival are currently lacking. Clinical features are heterogeneous and although the overall prognosis is poor, survival can vary significantly between individuals. This reflects the need for an individualized treatment approach which incorporates accurate risk stratification. Though numerous prognostic scores exist, newer CMML-specific models incorporating molecular data should be favored. While asymptomatic, low-risk patients should be observed until their disease progresses, the majority of patients will require treatment. Due to a deficiency in treatments with disease-modifying capacity, any patient who requires treatment should be considered for enrollment in clinical trials evaluating novel therapeutic approaches. Allogeneic stem cell transplant (allo-SCT) remains the only current therapy with the potential to cure the disease and should be considered in most patients with intermediate- to high-risk disease. However, substantial risks are involved and, in part, because of advanced age at diagnosis, a minority of patients are candidates. Hypomethylating agents (HMAs) have become a preferred treatment approach, and should be used in those with cytopenias. Patients presenting with proliferative features can be treated with hydroxyurea to manage their symptoms and control leukocytosis, though HMAs can be incorporated as well, particularly in patients with higher risk disease. HMAs should also be considered in patients with a high burden of disease prior to proceeding with allo-SCT. Induction chemotherapy should be reserved for younger, healthy patients who have transformed to acute myeloid leukemia to induce remission prior to transplant. Supportive care utilizing transfusion support, erythropoiesis-stimulating agents, and infection prevention measures should be incorporated into the care of all patients.

Notes

Compliance with Ethical Standards

Conflict of Interest

Eric Padron has received research funding from Kura Oncology, Incyte Corporation, and KaloBios Pharmaceuticals.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human or animal subjects performed by any of the authors.

References and Recommended Reading

Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance

1.

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